The recent confirmation of a human screwworm case in Maryland has raised concerns about this parasitic threat re-emerging in the US. Once eradicated, the screwworm is now spreading from Central America, prompting questions about its impact on humans, livestock, and what measures are being taken to prevent an outbreak. Below, we answer the most common questions about this dangerous parasite and what it means for the US.
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What is the screwworm and how did it reach the US?
The screwworm is a parasitic fly whose larvae burrow into living flesh, causing severe damage. It was eradicated in the US in the 1960s but has been spreading in Central America and Mexico since 2023. The recent human case in Maryland indicates it is now making its way northward, likely through infected livestock or travelers returning from affected regions.
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Could the screwworm affect humans or only livestock?
While the screwworm primarily infests livestock, it can also affect humans. The recent case in Maryland involved a person who had recently traveled from El Salvador. Infestations can be painful and require medical treatment, but the risk to the general public remains low if proper precautions are taken.
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What measures are being taken to prevent an outbreak?
The US is implementing strict control measures, including plans to establish a sterile fly facility in Texas. This facility will produce sterile screwworms to reduce wild populations and prevent the parasite from establishing itself in the US. Additionally, import restrictions and increased surveillance are in place to monitor and contain the spread.
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Should I be worried about this parasite in my area?
At this stage, the risk to the general public is considered low. However, farmers and those working with livestock should stay alert for signs of screwworm infestation. Authorities are actively monitoring the situation, and precautions are being taken to prevent further spread.
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How dangerous is a screwworm infestation?
A screwworm infestation can be very painful and damaging, especially if untreated. In livestock, it causes severe tissue damage and economic losses. In humans, it can lead to painful wounds and infections. Prompt medical or veterinary treatment is essential to manage infestations effectively.
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What should I do if I suspect a screwworm infestation?
If you notice unusual wounds or larvae on livestock or yourself, contact a healthcare provider or veterinarian immediately. Early detection and treatment are crucial to prevent serious complications and help control the spread of this parasite.